Often, media handing devices use drum storage escrows to hold notes while a transaction is authorized. All these escrow devices suffer from a common weakness in their design, which makes them prone to jams. The position of the drum is set to accommodate a maximum transaction size but, the vast majority transactions are much smaller.
In fact, existing escrow devices attempt to transport the media across a distance between the drive and drum that is typically 1.5 to 2 times the normal transport pitch. This is forced by the change in size of the escrow drum as the drum moves from empty to full. The drum must be far enough away from the media transport exit to provide clearance even when the drum is at its full capacity. Consequently, jams in conventional escrow devices are always a series maintenance issue in the media handling device. Usually, second line service calls are initiated for support personnel, and the escrow device is typically damaged.
The media is often fired from its position on the drum, but when the drum is too far away from the media exit, there is a hope that the media will properly get to the exit without jamming the escrow device. The drum remains fixed during transactions, which is a major issue for many conventional transactions.
As a result, conventional escrow devices are problematic and service intensive modules within media handling devices.